U.S. patent application number 15/196539 was filed with the patent office on 2017-01-05 for method and device for acquiring iris image.
This patent application is currently assigned to Xiaomi Inc.. The applicant listed for this patent is Xiaomi Inc.. Invention is credited to Zhijun Chen, Fei Long, Tao Zhang.
Application Number | 20170006216 15/196539 |
Document ID | / |
Family ID | 54120579 |
Filed Date | 2017-01-05 |
United States Patent
Application |
20170006216 |
Kind Code |
A1 |
Zhang; Tao ; et al. |
January 5, 2017 |
METHOD AND DEVICE FOR ACQUIRING IRIS IMAGE
Abstract
A method for acquiring an iris image is provided. The method
includes: acquiring an image including an eye of a person;
identifying a position of an eyeball in the image; determining a
parameter for photographing an iris based on the position of the
eyeball; and capturing the iris image based on the parameter.
Inventors: |
Zhang; Tao; (Beijing,
CN) ; Long; Fei; (Beijing, CN) ; Chen;
Zhijun; (Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Xiaomi Inc. |
Beijing |
|
CN |
|
|
Assignee: |
Xiaomi Inc.
|
Family ID: |
54120579 |
Appl. No.: |
15/196539 |
Filed: |
June 29, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06T 2207/10004
20130101; G06K 9/00604 20130101; G06T 2207/10048 20130101; G06T
2207/20081 20130101; G06K 9/2018 20130101; G06T 2207/30201
20130101; H04N 5/332 20130101; H04N 5/23219 20130101; G06K 9/3241
20130101 |
International
Class: |
H04N 5/232 20060101
H04N005/232; G06T 7/00 20060101 G06T007/00; H04N 5/33 20060101
H04N005/33; G06K 9/00 20060101 G06K009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 30, 2015 |
CN |
201510373998.4 |
Claims
1. A method for acquiring an iris image, comprising: acquiring an
image including an eye of a person; identifying a position of an
eyeball in the image; determining a parameter for photographing an
iris based on the position of the eyeball; and capturing the iris
image based on the parameter.
2. The method according to claim 1, wherein identifying the
position of the eyeball comprises: identifying a position of the
eye in the image; and identifying a position of a center of the
eyeball and a radius of the eyeball based on the position of the
eye.
3. The method according to claim 2, wherein identifying the
position of the eye in the image comprises: identifying a region in
the image containing the eye based on an AdaBoost algorithm.
4. The method according to claim 3, wherein the position of the
center of the eyeball and the radius of the eyeball are identified
by performing a radial symmetry transform (RST) in the region.
5. The method according to claim 1, wherein determining the
parameter for capturing the iris image comprises: acquiring a
predetermined eyeball radius; and determining a focal point and a
focal length for capturing a near-infrared iris image based on a
position of a center of the eyeball and the predetermined eyeball
radius.
6. The method according to claim 1, wherein acquiring the image
comprises: photographing the eye of the person to obtain the
image.
7. The method according to claim 1, wherein the iris image is a
near-infrared image, and the parameter is used for capturing the
near-infrared image.
8. The method according to claim 1, wherein the image is acquired
by using a visible light camera, and the iris image is captured by
using a near-infrared camera.
9. The method according to claim 1, wherein the image is acquired
by using a near-infrared camera, and the iris image is captured by
using the near-infrared camera.
10. A device for acquiring an iris image, comprising: a processor;
and a memory for storing an instruction executable by the
processor, wherein the processor is configured to: acquire an image
including an eye of a person; identify a position of an eyeball in
the image; determine a parameter for photographing an iris based on
the position of the eyeball; and cause the iris image to be
captured based on the parameter.
11. The device according to claim 10, wherein the processor is
further configured to: identify a position of the eye in the image;
and identify a position of a center of the eyeball and a radius of
the eyeball based on the position of the eye.
12. The device according to claim 11, wherein the processor is
further configured to: identify a region in the image containing
the eye based on an AdaBoost algorithm.
13. The device according to claim 12, wherein the processor is
further configured to: perform a radial symmetry transform (RST) in
the region to identify the position of the center of the eyeball
and the radius of the eyeball.
14. The device according to claim 10, wherein the processor is
further configured to: acquire a predetermined eyeball radius; and
determine a focal point and a focal length for capturing a
near-infrared iris image based on a position of a center of the
eyeball and the predetermined eyeball radius in the image.
15. The device according to claim 10, wherein the image is obtained
by photographing the eye of the person.
16. The device according to claim 10, wherein the iris image is a
near-infrared image, and the parameter is used for capturing the
near-infrared image.
17. The device according to claim 10, further comprising: a visible
light camera configured to capture the image; and a near-infrared
camera configured to capture the iris image.
18. The device according to claim 10, further comprising: a
near-infrared camera configured to capture the image and the iris
image.
19. A non-transitory computer-readable storage medium having stored
therein instructions that, when executed by a processor of a
device, cause the device to perform a method for acquiring an iris
image, the method comprising: acquiring an image including an eye
of a person; identifying a position of an eyeball in the image;
determining a parameter for photographing an iris based on the
position of the eyeball; and capturing the iris image based on the
parameter.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims a priority to
Chinese Patent Application No. 201510373998.4, filed Jun. 30, 2015,
the entire contents of which are incorporated herein by
reference.
TECHNICAL FIELD
[0002] The present disclosure generally relates to the field of
image acquisition and, more particularly, to a method and a device
for acquiring an iris image.
BACKGROUND
[0003] Iris recognition technique has been widely applied to the
field of biometric identification for its high uniqueness. However,
the conventional method for acquiring an iris image requires a user
attach an eye to an iris acquisition apparatus and actively
coordinate with the iris acquisition apparatus, resulting in
difficulty in using the iris acquisition apparatus.
SUMMARY
[0004] According to a first aspect of the present disclosure, there
is provided a method for acquiring an iris image, comprising:
acquiring an image including an eye of a person; identifying a
position of an eyeball in the image; determining a parameter for
photographing an iris based on the position of the eyeball; and
capturing the iris image based on the parameter.
[0005] According to a second aspect of the present disclosure,
there is provided a device for acquiring an iris image, comprising:
a processor; and a memory for storing instructions executable by
the processor. The processor is configured to: acquire an image
including an eye of a person; identify a position of an eyeball in
the image; determine a parameter for photographing an iris based on
the position of the eyeball; and cause the iris image to be
captured based on the parameter.
[0006] According to a third aspect of the present disclosure, there
is provided a non-transitory computer-readable storage medium
having stored therein instructions that, when executed by a
processor of a device, cause the device to perform a method for
acquiring an iris image, the method comprising: acquiring an image
including an eye of a person; identifying a position of an eyeball
in the image; determining a parameter for photographing an iris
based on the position of the eyeball; and capturing the iris image
based on the parameter.
[0007] It is to be understood that both the foregoing general
description and the following detailed description are illustrative
and explanatory only and are not restrictive of the disclosure, as
claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate embodiments
consistent with the disclosure and, together with the description,
serve to explain the principles of the disclosure.
[0009] FIG. 1 is a flowchart of a method for acquiring an iris
image, according to an exemplary embodiment.
[0010] FIG. 2 is a block diagram of a device for acquiring an iris
image, according to an exemplary embodiment.
[0011] FIG. 3 is a block diagram of another device for acquiring an
iris image, according to an exemplary embodiment.
[0012] FIG. 4 is a block diagram of another device for acquiring an
iris image, according to an exemplary embodiment.
[0013] FIG. 5 is a block diagram of a device for identifying an
iris, according to an exemplary embodiment.
[0014] FIG. 6 is a block diagram of a device for acquiring an iris
image, according to an exemplary embodiment.
DETAILED DESCRIPTION
[0015] Reference will now be made in detail to exemplary
embodiments, examples of which are illustrated in the accompanying
drawings. The following description refers to the accompanying
drawings in which the same numbers in different drawings represent
the same or similar elements unless otherwise represented. The
implementations set forth in the following description of exemplary
embodiments do not represent all implementations consistent with
the disclosure. Instead, they are merely examples of apparatuses
and methods consistent with aspects related to the disclosure as
recited in the appended claims.
[0016] FIG. 1 is a flowchart of a method 100 for acquiring an iris
image, according to an exemplary embodiment. The method 100 may be
performed by a device such as a mobile phone, a computer, a digital
broadcast terminal, a messaging device, a gaming console, a tablet,
a medical device, exercise equipment, a personal digital assistant,
and the like. Referring to FIG. 1, the method 100 includes the
following steps.
[0017] In step S101, the device acquires an image including an eye
of a person.
[0018] For example, the step S101 may be implemented by
photographing a person's eye to obtain an image. In some
implementations, an AdaBoost classifier may be used to rapidly
detect an area containing the eye, and the area containing the eye
may be photographed for one or multiple times, so as to obtain one
or more images including the eye. In some implementations, a
visible light camera may be used for capturing the image.
[0019] In step S102, the device identifies a position of an eyeball
in the image. For example, the device may identify the position of
the eyeball by performing image recognition on the image.
[0020] In some embodiments, the device may identify a position of
an eye in the image and determine a position of a center of the
eyeball and a radius of the eyeball based on the eye position. For
example, a Radical Symmetry Transform (RST) method may be used to
identify the position of the eyeball, in which a circle is detected
by calculating a gradient of each point in multiple images and
subjecting all points in a radial direction to cumulative voting
reversely such that the most votes are cumulated at the center of
the eyeball.
[0021] In some embodiments, an AdaBoost algorithm may be used to
identify a region containing the eye, and an RST may be performed
in the identified region to determine the position of the center of
the eyeball and the eyeball radius.
[0022] In step S103, the device determines a parameter for
photographing an iris based on the position of the eyeball.
[0023] In some embodiments, the parameter may include a focal point
position, a focal length, brightness and contrast, and the like,
for obtaining a clear iris image with an appropriate size. For
example, when the image is acquired by using a visible light
camera, based on the position of the center of the eyeball, the
device may determine a distance between the camera and the eyeball
center position as 30 cm and current ambient brightness as 100
cd/m.sup.2. Correspondingly, the focal length, brightness level,
and contrast level for photographing the iris may be set as 8, -20,
and 18, respectively.
[0024] In some embodiments, a focal point and a focal length for
capturing a near-infrared image may be determined based on the
position of the center of the eyeball and a predetermined eyeball
radius, such that it is not required to determine the eyeball
radius in the acquired image. As the eyeball radius does not vary
significantly for each individual, an average value of the eyeball
radius for a person may be stored in advance, thereby improving
implementation efficacy of the method.
[0025] In step S104, the device captures an iris image based on the
parameter. For example, the device may capture the iris image by
photographing the iris based on the parameter.
[0026] In some embodiments, a near-infrared camera may be used to
capture the iris image based on a near-infrared parameter
determined in step S103, thereby improving clarity of the iris
image.
[0027] In the method 100, the parameter for capturing the iris
image is determined based on an image of the eye that can be
acquired by a visible light camera, without requiring the user to
adhere his eye to a specific position or to actively cooperate with
an iris acquisition apparatus thereby improving the user
experience.
[0028] FIG. 2 is a block diagram of a device 200 for acquiring an
iris image, according to an exemplary embodiment. Referring to FIG.
2, the device 200 includes an acquiring module 210, an identifying
module 220, a determining module 230, and a capturing module
240.
[0029] The acquiring module 210 is configured to acquire an image
including an eye of a person. The identifying module 220 is
configured to identify a position of an eyeball in the image. For
example, the identifying module 220 may be configured to identify
the position of the eyeball by performing image recognition on the
image. The determining module 230 is configured to determine, based
on the position of the eyeball, a parameter for photographing an
iris. The capturing module 240 is configured to captures an iris
image based on the parameter.
[0030] FIG. 3 is a block diagram of another device 300 for
acquiring an iris image, according to an exemplary embodiment.
Referring to FIG. 3, the device 300 includes the acquiring module
210, identifying module 220, determining module 230, and capturing
module 240, where the identifying module 220 includes a first
identifying sub-module 221 and a second identifying sub-module
222.
[0031] The first identifying sub-module 221 is configured to
identify a position of the eye in the image. The second identifying
sub-module 222 is configured to identify a position of a center of
an eyeball and a radius of the eyeball based on the position of the
eye. In some embodiments, the first identifying sub-module 221 is
further configured to identify a region in the image containing the
eye based on a self-adaptive AdaBoost algorithm. The second
identifying sub-module 222 may be further configured to identify
the position of the eyeball center and the eyeball radius by
performing a RST in the region.
[0032] FIG. 4 is a block diagram of another device 400 for
acquiring an iris image, according to an exemplary embodiment.
Referring to FIG. 4, the device 400 includes the acquiring module
210, identifying module 220, determining module 230, and capturing
module 240, where the determining module 230 includes a first
determining sub-module 231 and a second determining sub-module 232,
the acquiring module 210 includes an acquiring sub-module 211, and
the capturing module 240 includes a capturing sub-module 241.
[0033] The first determining sub-module 231 is configured to
acquire a predetermined eyeball radius and determine a focal point
and a focal length for capturing a near-infrared iris image based
on the position of the center of the eyeball and the predetermined
eyeball radius.
[0034] The second determining sub-module 232 is configured to
determine a parameter for capturing a near-infrared iris image
based on the position of the eyeball parameter in the image.
Corresponding, the capturing sub-module 241 is configured to
capture the near-infrared iris image based on the parameter.
[0035] The acquiring sub-module 211 is configured to photograph an
eye of a person to obtain the image including the eye.
[0036] FIG. 5 is a block diagram of a device 500 for identifying an
iris, according to an exemplary embodiment. Referring to FIG. 5,
the device 500 includes a first capturing component 510, a
processing component 520, and a second capturing component 530.
[0037] The first capturing component 510 is configured to capture
an image of an eye. The processing component 520 is configured to
determine a position of an eyeball in the image and determine a
parameter for photographing an iris based on the eyeball position.
The second capturing component 530 is configured to capture an iris
image based on the parameter and send the iris image to the
processing component 520. The processing component 520 is further
configured to identify iris feature information from the iris image
and determine whether the iris feature information matches
predetermined iris feature information.
[0038] In some embodiments, the first capturing component 510 is a
visible light camera, and the second capturing component 530 is a
near-infrared camera.
[0039] In other embodiments, the first capturing component 510 and
the second capturing component 530 may be the same near-infrared
camera.
[0040] FIG. 6 is a block diagram of a device 600 for acquiring an
iris image, according to an exemplary embodiment. For example, the
device 600 may be a mobile phone, a computer, a digital broadcast
terminal, a message receiving and sending device, a gaming console,
a tablet, a medical device, exercise equipment, a personal digital
assistant, a vehicle mobile terminal, and the like.
[0041] Referring to FIG. 6, the device 600 may include one or more
of the following components: a processing component 602, a memory
604, a power supply component 606, a multimedia component 608, an
audio component 610, an input/output (I/O) interface 612, a sensor
component 614, and a communication component 616. The person
skilled in the art should appreciate that the structure of the
device 600 as shown in FIG. 6 does not intend to limit the device
600. The device 600 may include more or less components or combine
some components or other different components.
[0042] The processing component 602 typically controls overall
operations of the device 600, such as the operations associated
with display, telephone calls, data communications, camera
operations, and recording operations. The processing component 602
may include one or more processors 620 to execute instructions to
perform all or part of the steps in the above described methods.
Moreover, the processing component 602 may include one or more
modules which facilitate the interaction between the processing
component 602 and other components. For instance, the processing
component 602 may include a multimedia module to facilitate the
interaction between the multimedia component 608 and the processing
component 602.
[0043] The memory 604 is configured to store various types of data
to support the operation of the device 600. Examples of such data
include instructions for any applications or methods operated on
the device 600, contact data, phonebook data, messages, images,
video, etc. The memory 604 is also configured to store programs and
modules. The processing component 602 performs various functions
and data processing by operating programs and modules stored in the
memory 604. The memory 604 may be implemented using any type of
volatile or non-volatile memory devices, or a combination thereof,
such as a static random access memory (SRAM), an electrically
erasable programmable read-only memory (EEPROM), an erasable
programmable read-only memory (EPROM), a programmable read-only
memory (PROM), a read-only memory (ROM), a magnetic memory, a flash
memory, a magnetic or optical disk.
[0044] The power supply component 606 is configured to provide
power to various components of the device 600. The power supply
component 606 may include a power management system, one or more
power sources, and any other components associated with the
generation, management, and distribution of power in the device
600.
[0045] The multimedia component 608 includes a screen providing an
output interface between the device 600 and a user. In some
embodiments, the screen may include a liquid crystal display (LCD)
and/or a touch panel (TP). If the screen includes the touch panel,
the screen may be implemented as a touch screen to receive input
signals from the user. The touch panel includes one or more touch
sensors to sense touches, swipes, and gestures on the touch panel.
The touch sensors may not only sense a boundary of a touch or swipe
action, but also sense a period of time and a pressure associated
with the touch or swipe action. In some embodiments, the multimedia
component 608 includes a front camera and/or a rear camera. The
front camera and/or the rear camera may receive an external
multimedia datum while the device 600 is in an operation mode, such
as a photographing mode or a video mode. Each of the front camera
and the rear camera may be a fixed optical lens system or have
focus and optical zoom capability. In some embodiments, the
multimedia component 608 may include a visible light camera and/or
a near-infrared camera. The visible light camera may be used to
capture an image including an eye of a person. The near-infrared
camera may be used to capture an iris image by photographing an
iris using a parameter determined by the processing component 602.
The near-infrared camera may also be used to capture an image
including an eye of a person.
[0046] The audio component 610 is configured to output and/or input
audio signals. For example, the audio component 610 includes a
microphone configured to receive an external audio signal when the
device 600 is in an operation mode, such as a call mode, a
recording mode, and a voice recognition mode. The received audio
signal may be further stored in the memory 604 or transmitted via
the communication component 616. In some embodiments, the audio
component 610 further includes a speaker to output audio
signals.
[0047] The I/O interface 612 provides an interface between the
processing component 602 and peripheral interface modules, such as
a keyboard, a click wheel, buttons, and the like. The buttons may
include, but are not limited to, a home button, a volume button, a
starting button, and a locking button.
[0048] The sensor component 614 includes one or more sensors to
provide status assessments of various aspects of the device 600.
For instance, the sensor component 614 may detect an on/off state
of the device 600, relative positioning of components, e.g., the
display and the keypad, of the device 600, a change in position of
the device 600 or a component of the device 600, a presence or
absence of user contact with the device 600, an orientation or an
acceleration/deceleration of the device 600, and a change in
temperature of the device 600. The sensor component 614 may include
a proximity sensor configured to detect the presence of nearby
objects without any physical contact. The sensor component 614 may
also include a light sensor, such as a CMOS or CCD image sensor,
for use in imaging applications. In some embodiments, the sensor
component 614 may also include an accelerometer sensor, a gyroscope
sensor, a magnetic sensor, a pressure sensor, or a temperature
sensor.
[0049] The communication component 616 is configured to facilitate
communication, wired or wirelessly, between the device 600 and
other devices. The device 600 can access a wireless network based
on a communication standard, such as WiFi, 2G, 3G, 4G, or a
combination thereof. In one exemplary embodiment, the communication
component 616 receives a broadcast signal or broadcast information
from an external broadcast management system via a broadcast
channel. In one exemplary embodiment, the communication component
616 further includes a near field communication (NFC) module to
facilitate short-range communications. For example, the NFC module
may be implemented based on a radio frequency identification (RFID)
technology, an infrared data association (IrDA) technology, an
ultra-wideband (UWB) technology, a Bluetooth (BT) technology, and
other technologies.
[0050] In exemplary embodiments, the device 600 may be implemented
with one or more application specific integrated circuits (ASICs),
digital signal processors (DSPs), digital signal processing devices
(DSPDs), programmable logic devices (PLDs), field programmable gate
arrays (FPGAs), controllers, micro-controllers, microprocessors, or
other electronic components, for performing the above described
methods for acquiring the iris image.
[0051] In exemplary embodiments, there is also provided a
non-transitory computer-readable storage medium including
instructions, such as included in the memory 604, executable by the
processor 620 in the device 600, for performing the above-described
methods. For example, the non-transitory computer-readable storage
medium may be a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy
disc, an optical data storage device, and the like.
[0052] It should be understood by those skilled in the art that the
above described modules can each be implemented through hardware,
or software, or a combination of hardware and software. One of
ordinary skill in the art will also understand that multiple ones
of the above described modules may be combined as one module, and
each of the above described modules may be further divided into a
plurality of sub-modules.
[0053] Other embodiments of the disclosure will be apparent to
those skilled in the art from consideration of the specification
and practice of the disclosure disclosed here. This application is
intended to cover any variations, uses, or adaptations of the
disclosure following the general principles thereof and including
such departures from the present disclosure as come within known or
customary practice in the art. It is intended that the
specification and examples be considered as illustrative only, with
a true scope and spirit of the disclosure being indicated by the
following claims.
[0054] It will be appreciated that the present disclosure is not
limited to the exact construction that has been described above and
illustrated in the accompanying drawings, and that various
modifications and changes can be made without departing from the
scope thereof. It is intended that the scope of the disclosure only
be limited by the appended claims.
* * * * *